Chronic obstructive pulmonary disease (COPD) is the third leading cause of death worldwide. Approximately 100 million people in China have COPD, yet the early diagnosis rate remains below 13%. This multicenter retrospective study will collect previously acquired dynamic chest radiography (DCR) images, pulmonary function test results, chest computed tomography images, symptom scores, clinical data, and follow-up outcomes from participating centers. A standardized multicenter retrospective DCR-COPD database will be established to systematically evaluate the utility of DCR-derived parameters for characterizing dynamic functional imaging phenotypes, assessing disease severity, and predicting the risk of COPD progression. The study will also provide a foundation for model development and subsequent prospective multicenter validation.
